+++
title = "Updates in June 2019"
date = 2019-07-06
aliases = ["status-update/2019-06-04/index.html"]
+++

This post gives an overview of the recent updates to the _Writing an OS in Rust_ blog and the used libraries and tools.

My focus this month was to finish the [_Heap Allocation_](./second-edition/posts/10-heap-allocation/index.md) post, on which I had been working since March. I originally wanted to include a section about different allocator designs (bump, linked list, slab, …) and how to implement them, but I decided to split it out into a separate post because it became much too long. I try to release this half-done post soon.

Apart from the new post, there were some minor updates to the `x86_64`, `bootloader` and `cargo-xbuild` crates. The following gives a short overview of notable changes to the different projects.

## blog_os

- [Use misspell tool to look for common typos](https://github.com/phil-opp/blog_os/pull/617)
- [New post about heap allocation](https://github.com/phil-opp/blog_os/pull/625)

## x86_64

- [Add ring-3 flag to GDT descriptor](https://github.com/rust-osdev/x86_64/pull/77) by [@mark-i-m](https://github.com/mark-i-m) (released as version 0.7.1)
- [Add bochs magic breakpoint, read instruction pointer, inline instructions](https://github.com/rust-osdev/x86_64/pull/79) by [@64](https://github.com/64)

## bootloader

- [Make the physical memory offset configurable through a `BOOTLOADER_PHYSICAL_MEMORY_OFFSET` environment variable](https://github.com/rust-osdev/bootloader/pull/58)
- [Use a stripped copy of the kernel binary (debug info removed) to reduce load times](https://github.com/rust-osdev/bootloader/pull/59) (released as version 0.6.1)

<!-- ## Bootimage -->

## cargo-xbuild

- [Document the XBUILD_SYSROOT_PATH environment variable](https://github.com/rust-osdev/cargo-xbuild/commit/994b5e75e1a4062cf506700e0ff38d5404338a37)
- [Fix incorrect joining of paths that caused some problems on Windows](https://github.com/rust-osdev/cargo-xbuild/commit/a1ff03311dd74447e8e845b4b96f2e137850027d)
